Jim Allchin, the former co-president of Microsoft’s Platforms and Service division has been subpoenaed in the Vista Capable class action lawsuit.

For those of you that haven’t been following the case, back in 2006 Microsoft came up with the idea that computers would be rated with two-tiers of performance when upgrading to Vista. Those that could only run the most basic features would be “Vista Capable” and those that could handle all the features would be “Premium Ready.”

The suit alleges that the “Vista Capable” campaign lead consumers to believe that a system was actually capable of running any version of Vista when it wasn’t. Vista Capable systems could only run Vista Home Basic and could not be expected to run all the features of the up-market versions of Vista even if they were upgraded. It is also said that Microsoft lowered the required specs for Vista to help Intel sell its lower-end graphics chips; this helped Microsoft to install Vista on systems that were not really capable of running it.

Several Microsoft executives claim they were mislead by their company’s own advertising campaign. Some even wanted to call Vista Home Basic, “Windows 2006? - leading some to believe that internally, Vista Home Basic wasn’t really Vista in the eyes of Microsoft.